Spark Plug Inspection - Yamaha BIG BEAR YFM400FPP Owner's Manual

1. Spark plug cap
1. Capuchon de bougie
1. Tapa de bujía
1. Spark plug wrench
1. Clé à bougie
1. Llave de bujías

Spark plug inspection

Removal
1. Remove the spark plug cap.
2. Use the spark plug wrench in the tool kit to re-
move the spark plug as shown.
Inspection
The spark plug is an important engine component
and is easy to inspect. The condition of the spark
plug can indicate the condition of the engine.
The ideal color on the white insulator around the
center electrode is a medium-to-light tan color for a
ATV that is being ridden normally.
Do not attempt to diagnose such problems your-
self. Instead, take the ATV to a Yamaha dealer.
You should periodically remove and inspect the
spark plug because heat and deposits will cause
the spark plug to slowly break down and erode. If
electrode erosion becomes excessive, or if carbon
and other deposits are excessive, you should re-
place the spark plug with the specified plug.
Specified spark plug:
DR8EA (NGK)
8-37
EBU00680